Fabrication methods of a transparent conductive electrode (301) and an array substrate are provided. The fabrication method of the transparent conductive electrode (301) comprises: forming a sacrificial layer pattern (201) on a substrate (10) having a first region (A1) and a second region (A2) adjacent to each other, wherein the sacrificial layer pattern (201) is located in the second region (A2), and has an upper sharp corner profile formed on a side adjacent to the first region (A1); forming a transparent conductive thin-film (30) in the first region (A1) and the second region (A2) of the substrate (10) with the sacrificial layer pattern (201) formed thereon, wherein a thickness ratio of the transparent conductive thin-film (30) to the sacrificial layer pattern (201) is less than or equal to 1:1.5, and the transparent conductive thin-film (30) is disconnected at the upper sharp corner profile of the sacrificial layer pattern (201), such that at least a part of a side surface of the sacrificial layer pattern (201) facing the first region (A1) is exposed; and removing the sacrificial layer pattern (201) so as to reserve the transparent conductive thin-film (30) in the first region as the transparent conductive electrode (301).